Automatic applicator for liquid pharmaceutical preparations, particularly  for insulin

ABSTRACT

An automatic applicator for liquid pharmaceutical preparations, particularly for multiple injection application of set doses of a medicine from an exchangeable container is provided. The automatic applicator includes a body housing connected to a housing of an exchangeable container with a medicine having a plunger, the said plunger being displaced only linearly by an integrated driving unit, suitable for immobilizing, driving, leading linearly and blocking rotation of the plunger, driven via a double action clutch, by a tensioning spring situated in the body housing, the spring tensioned by a rotary hand-dose-setting ring via the double action clutch, wherein the driving unit is activated by a trigger unit and a dose is indicated by an indicating arrangement. The automatic applicator further includes at least one block key placed in an upper part of a ratchet barrel, collaborating with at least one key placed in an internal part of the body housing.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/EP2010/054128, filed on Mar. 29, 2010, which claims the benefit ofP.389427, filed on Oct. 30, 2009. The disclosures of the aboveapplications are incorporated herein by reference.

FIELD

The present disclosure concerns an automatic applicator for liquidpharmaceutical preparations, particularly for insulin, more particularlyfor multiple injection application of set doses of a medicine from anexchangeable container, for example for the self-application of insulinby diabetes patients.

BACKGROUND

The European patent EP 0338 806 (Holman and Marchall) teaches a syringecomprising a body, a dose-setting device in the form of a rotary cap orring mounted on the body and capable of being moved to a selected setposition where a latch is arranged to retain the setting device in thatset position, the movement of the setting device being accompanied bystraining of a spring, which, when the latch is released, provides theforce for expelling the set dose, characterized by means arranged torelease the latch, which causes the return of the setting device to anoriginal position to drive a plunger through a one-way clutch to expelthe set dose; and by a quick pitch screw thread arrangement capable oftransforming rotation of the setting device into linear movement of theplunger.

Also Polish patent application P 341 395 teaches a syringe fordistribution of set doses of a medicine from a cartridge containing theamount of the medicine sufficient to prepare several treatment doses,comprising a housing, a piston rod having noncircular cross-section andan external screw thread, a piston rod drive arrangement comprising twoelements, i.e. piston rod leaders and a nut with an internal screwthread corresponding to the piston rod external screw thread, as well asa dose-setting mechanism comprising non-self-blocking screw threadconnection, along which an injection push-button is unscrewed from thenearer housing end, causing rotation of the dose-setting element. Thissyringe is characterized in that between the nut and the piston rodleaders there is unidirectional coupling enabling the rotation of boththese parts in one direction but not in the opposite direction, whereinthe allowed rotation is the only one, by means of which the piston rodis moved in the circumferential direction in the syringe. The couplingis designed in such way that the initial resistance, sufficient toresist the torque exerted on the coupling by setting a dose, has to beovercome to allow rotation. The marks indicating the size of theselected dose could be placed under the housing.

The main disadvantage of the known devices is lack of the provision ofapplication of the precisely controlled and set dose of a medicine.

The above discussed syringe for manual application of a medicinerequires from a patient the manual adjustment of the pressure force onthe injection push-button, which defines the speed of the injection.This causes additional stress and discomfort at application. Anadditional disadvantage is a complex arrangement to transform the lineardisplacement of the injection pushbutton into the linear displacement ofthe piston rod by means of the rotary movement of the nut. Otherdisadvantages of a syringe for an application of a medicine using atensioned spring comprise the failure prone construction of the triggerdevice, which does not ensure reliable nut blocking, and the lack of anexternal guiding means for the tensioned spring. This negatively affectsmaintaining the control and the precision of the application of the setdose of a medicine.

Besides, known devices do not ensure adequate protection againstdamaging the clutch or the driving arrangement due to excessive rotationof the dose-setting element. Also, forces of friction opposing theaction of the plunger are too large. The arrangements for doseindication in known devices are too complex and the scale usually placedon the external surface of the housing can be easily effaced.

SUMMARY

One aim of the present disclosure concerning an automatic applicatorparticularly for insulin, more particularly for multiple injectionapplication of set doses of a medicine from an exchangeable container,is to ensure a capability for the precisely controlled application ofthe set dose of a medicine, preserving an automatic application of themedicine without any stress, providing external guidance for thetensioned spring and providing adequate protection against damaging theclutch or the driving arrangement due to excessive rotation of thedose-setting element.

Another aim of the present disclosure is to ensure the reduction offorces of friction opposing the action of the plunger and providereliable nut blocking by means of a reliable construction of a triggerdevice, preserving an automatic application of the medicine.

Yet another aim of the present invention concerning an automaticapplicator is to ensure an indicator device having the scale marksplaced not on the external surface of the housing, which preventseffacing them during the operating of the applicator by its user.

An automatic applicator for liquid pharmaceutical preparations isprovided, particularly for insulin, more particularly for multipleinjection application of set doses of a medicine from an exchangeablecontainer, comprising a body housing connected to a housing of anexchangeable container with a medicine, particularly insulin, having aplunger, suitable for expelling the medicine, a plunger being displacedlinearly by an integrated driving unit, suitable for immobilising,driving, leading linearly and blocking rotation of the plunger, drivenvia a double action clutch, by a tensioning spring situated in the bodyhousing, the spring tensioned by a rotary hand-dose-setting ring via thesame double action clutch unit, wherein the driving unit is activated bya trigger unit and a dose is indicated by an indicating arrangement.According to the present disclosure the automatic applicator comprisesat least one block key placed in the upper part of the ratchet barrel,collaborating with at least one key placed in the internal part of thecylindrical body housing.

The novel construction of the automatic applicator enables the preciselycontrolled application of the set dose of a medicine, preserving anautomatic application of the medicine without any stress, providingexternal guidance for the tensioned spring and providing adequateprotection against damaging the clutch or the driving arrangement due toexcessive rotation of the dose-setting element.

Advantageously the automatic applicator comprises two block keys placeddirectly on the circumferential surface of the ratchet barrel,collaborating with two keys on the internal part of the cylindricalsurface of the cylindrical body housing, placed above a viewing window.

An automatic applicator variant is provided wherein the integrateddriving unit, suitable for immobilizing, driving, leading linearly andblocking rotation of the plunger, comprises a plunger block guide and adriving nut, whereas the plunger block guide is blocked in a toothedring of the seat element, urged to it by means of the container housingof the exchangeable insulin container, and in the said integrateddriving unit a nut is bearingly mounted in a seat element,advantageously by means of a ball bearing.

Owing to such construction, there is provided reliable driving nutblocking, minimally affecting the positioning of the nut andsimultaneously preventing any its rotation or influencing the positionof the plunger during dose setting, as well as ensured the reduction offorces of friction opposing the action of the plunger.

Further, advantageously the driving tensioning spring is a twistedspring and the second spring is placed directly under the trigger unit.

A further automatic applicator variant is provided, in which theindicating arrangement comprises a scale deposited linearly on acylindrical part of the ratchet barrel under the block keys and ainspection window situated in the housing. Owing to such construction,the scale is appropriately displaced during dose setting and is wellvisible in the inspection window.

DRAWINGS

In order that the disclosure may be well understood, there will now bedescribed various forms thereof, given by way of example, referencebeing made to the accompanying drawings, in which:

FIG. 1 presents the longitudinal section of the automatic applicator,without an exchangeable container and its casing;

FIG. 2 presents the cross-section B-B of the ratchet mechanism of theautomatic applicator with the pawls meshed with the toothed ring of thenut;

FIG. 3 presents the cross-section C-C of the automatic applicator fromthe FIG. 1, in the place, in which the trigger mechanism meshes with thetoothed ring of the nut;

FIG. 4 presents the cross-section 0-0 of the automatic applicator fromthe FIG. 1, showing the system blocking the rotation of the scale, whichdefines the working range of the automatic applicator;

FIG. 5 presents pictorially the cross-section E-E of the automaticapplicator from the FIG. 1, showing the positioning of the elements ofthe arrangement blocking the plunger against rotation;

FIG. 6 presents the front axonometric view of the automatic applicatorfrom the FIG. 1, with parts of the housings removed, showing theadvantageous mutual positioning of the elements of the internalmechanisms of the automatic applicator; and

FIG. 7 presents the exploded front axonometric view of the automaticapplicator from the FIG. 1.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses.

As shown in the FIGS. 1, 6 and 7, an automatic applicator for liquidpharmaceutical preparations, particularly for insulin, more particularlyfor multiple injection application of set doses of a medicine from anexchangeable container, comprises the body housing 1, connected to thehousing 2 of the exchangeable container with a medicine (not shown inthe drawings). The insulin is expelled by the plunger 12, linearlydisplaced by means of the driving unit, suitable for immobilizing,driving, leading linearly and blocking rotation of the plunger 12,driven via a double clutch unit by the tensioning spring 15, wherein thedriving tensioning spring 15 is a twisted spring situated in the bodyhousing 1, tensioned by the rotary hand-dose-setting ring 3 also via adouble clutch unit, wherein the driving unit is activated by the triggerunit 13 and the displaceable indicating cylinder 14 is situated on thetensioning spring holder 13 and a scale 5.7 with the scale visible inthe inspection window 1.1 deposited on the ratchet barrel 5.

The automatic applicator for liquid pharmaceutical preparations,particularly for insulin, more particularly for multiple injectionapplication of set doses of a medicine from an exchangeable container,operates as follows.

In order to replace the insulin container you should unscrew thecontainer housing 2, which is connected to the body housing 1 (FIG. 1)by turning it anticlockwise. After unscrewing the container housing 2,the plunger block guide 11 and the seat element 9 become automaticallydisengaged owing to the action of the disengaging spring 10 by means ofmoving the plunger block guide 11 coaxially in the direction of plunger12. This enables hand backing of the plunger 12 by using the force inthe axial direction to push it into the housing 1. The plunger ending12.1 is independently rotated on the plunger 12. The coupling betweenthe plunger 12 and the nut 7 is by a quick thread, so while being pushedinto the housing 1 the plunger 12 screws itself into the nut 7. Theplunger should be pushed until it almost completely hides in the housing1, which allows a new container with insulin to be inserted.

The nut 7 is coupled to the plunger 12 by a thread having pitch enablingapplication of the appropriate dose of insulin. Further, the nut 7 isbearingly mounted in the seat element 9, advantageously by means of aball bearing 8.

Then you should remove the needle (not shown) mounted on the containerhousing 2 by turning it anti-clockwise, remove the empty container bywithdrawing it from the housing 2 and install a new container.

To install a new container you should insert it into the containerhousing 2, which you should place in the body housing 1 by turning itclockwise. Next you should fix a new needle and cover it with theprotecting cap.

The dose-setting is carried out by turning the rotary hand-dose-settingring 3 (FIG. 1) clockwise. The currently set dose can be seen on thecylindrical part of the ratchet barrel 5 by means of the inspectionwindow 1.1 situated in the housing 1, which together with the scale 5.7deposited linearly on a under the block keys 5.6 comprises theindicating arrangement. The cylinder of the ratchet barrel 5 is scaledby every four units and the turning of the rotary hand-dose setting ring3 is accompanied by a characteristic clicking at every two units,corresponding to 0.02 ml of insulin. The dose-setting can be realized upto two units, wherein the scale 5.7 visible through the inspectionwindow 1.1, stops at any value or between the given dose values, whichis easy to check as two consecutive doses are then seen in inspectionwindow 1.1, and a red line indicator shows the position between them.

The rotary hand-dose-setting ring 3 is rigidly connected to the couplingsleeve 6. When a dose is to be increased, the coupling sleeve 6 (FIG. 2)is rotated clockwise (looking in the direction of the needle) whereinthe resilient arm of the pawl 5.3 is displaced on the slide edges 7.5 ofthe ratchet tooth ring 7.1 of the stationary driving nut 7, from oneblocking edge of the ratchet tooth ring 7.1 to the neighbour edge(s)depending on the angle of rotation. The ratchet barrel 5 is driven bythe coupling sleeve 6 by means of the steering recess 6.1 made in theinner wall of the coupling sleeve 6 meshed with the key 5.4 situated inthe inner wall of the ratchet barrel 5. Therefore, when the couplingsleeve 6 is rotated, the ratchet barrel 5 is rotated together with it.During the rotation in the clockwise direction, the resilient arm of thepawl 5.3 is displaced radially, alternatively inside and outside.

The ratchet barrel 5 is rigidly connected to the spring 15, which inturn is connected to spring block 4. The spring block 4 is rigidlyconnected to the housing 1 and secured against rotation.

During the dose setting the nut 7 is immobilized by the trigger unit 13by means of the rectangular grooves 7.7 (FIG. 3) situated on thecircumference of the nut 7, collaborating with the key 13.1 of thetrigger unit 13.

The operational range of the automatic applicator is defined by twoblock keys 5.6 (FIG. 4) placed directly on the circumferential surfaceof the ratchet barrel 5, collaborating with two keys 1.3 on the internalpart of the cylindrical surface of the cylindrical housing 1 placedabove the inspection window 1.1. The keys are situated on the oppositesides and simultaneously slightly displaced axially. Such arrangementenables realizing one incomplete rotation of the dose setting elements.

After setting the dose you can actuate the dosing of insulin by pressingthe trigger unit 13 in the direction of the needle. The trigger unit 13should be pressed throughout the whole time of the insulin application.The range of the trigger displacement is defined by the displacement ofthe key 13.1 in the corresponding groove 1.2 in the body housing 1.After pressing the trigger unit 13 the nut 7 is released by thedisengagement of the ring with the rectangular grooves 7.7 and the key13.1 of the trigger unit 13. The mechanism starts rotating, driven bythe force from the tensioning spring 15. The nut 7 causes the unscrewingof the plunger 12 on the thread 12.1 of the plunger 12, The rotation ofthe plunger is blocked by the key 11.1 of the plunger block guide 11 andthe recess 12.2 made in the plunger 12 (FIG. 5). The plunger 12 actsdirectly on the piston of the insulin container, placed in the containerhousing 2. It causes the injection of insulin from the needle mounted onthe container housing 2. This action is accompanied by the reversemovement of the whole mechanism to its initial position, i.e. thetensioning spring 15 unwinds, and the ratchet barrel 5 with the scale5.7 returns to the position “0”.

After completing the dose-setting you can release the trigger unit 13.The trigger unit 13 will then automatically return to its initialposition urged by the spring 14, which is placed directly under thetrigger unit 13, and will again block the nut 7.

The double action clutch, best seen in the FIG. 2, which presents thecross-section B-B of the ratchet mechanism of the automatic applicatorwith the pawls meshed with the toothed ring of the nut, comprises thecoupling sleeve 6 radially coupled with the body of the ratchet barrel 5and coupled with the pawls 5, 3 having hooks separately meshed with thegear ring 7.5 of the driving nut 7.

The coupling sleeve 6 is rigidly connected to the rotaryhand-dose-setting ring 3 and the body of the ratchet barrel 5 is rigidlyconnected to the tensioning spring 15 holder, in the form of aprotective sleeve, which enables transfer of the rotation of the rotaryhand-dose-setting ring 3 to the tensioning spring 15 holder.

The tensioning spring 15 (FIG. 1 and FIG. 6) is mounted, form the sideof the needle, in the tensioning spring 15 holder, in the form of aprotective sleeve rigidly connected to the body of the ratchet barrel 5.

The integrated driving unit (FIG. 5), suitable for immobilizing,driving, leading linearly and blocking rotation of the plunger 12comprises a plunger block guide 11 and a driving nut 7. The constructionof the integrated driving unit enables hand backing of the plunger 12 bypushing it into the driving nut 7 in such way that it minimallyprotrudes from the housing, allows a new container, ego with insulin, tobe inserted.

The nut 7 (as mentioned above) is coupled to the plunger 12 by a threadhaving pitch enabling application of the appropriate dose of insulin.Additionally, the plunger 12 comprises at least one longitudinal grooveenabling linear displacement of the plunger 12 in the plunger blockguide 11 by means of at least one key.

The trigger unit (FIG. 3) constitutes the trigger 13 with the key 13.1slidingly displaced in the groove 1.2 situated in the housing 1 in orderto block the ring with the rectangular grooves 7.7 of the driving nut 7.

It should be noted that the disclosure is not limited to the embodimentdescribed and illustrated as examples. A large variety of modificationshave been described and more are part of the knowledge of the personskilled in the art. These and further modifications as well as anyreplacement by technical equivalents may be added to the description andfigures, without leaving the scope of the protection of the disclosureand of the present patent.

1. An automatic applicator for liquid pharmaceutical preparations,particularly for insulin, more particularly for multiple injectionapplication of set doses of a medicine from an exchangeable container,comprising a body housing connected to a housing of an exchangeablecontainer with a medicine, particularly insulin, having a plunger,suitable for expelling the medicine, the plunger being displaced onlylinearly by an integrated driving unit, suitable for immobilizing,driving, leading linearly and blocking rotation of the plunger, drivenvia a double action clutch, by a tensioning spring situated in the bodyhousing, the spring tensioned by a rotary hand-dose-setting ring via thedouble action clutch, wherein the driving unit is activated by a triggerunit and a dose is indicated by an indicating arrangement, the bodyhousing comprising at least one block key placed in an upper part of aratchet barrel, collaborating with at least one key placed in aninternal part of the body housing.
 2. The automatic applicator accordingto claim 1 further comprising two block keys placed directly on acircumferential surface of the ratchet barrel, collaborating with twokeys on the internal part of a cylindrical surface of the body housing,placed above an inspection window.
 3. The automatic applicator accordingto claim 2, wherein the indicating arrangement comprises a scaledeposited linearly on a cylindrical part of the ratchet barrel under theblock keys and the inspection window.
 4. The automatic applicatoraccording to claim 1, wherein the integrated driving unit, suitable forimmobilizing, driving, leading linearly and blocking rotation of theplunger, comprises a nut bearingly mounted in a seat element.
 5. Theautomatic applicator according to claim 3, wherein the nut is bearinglymounted in the seat element by a ball bearing.
 6. The automaticapplicator according to claim 1, wherein the integrated driving unit,suitable for immobilizing, driving, leading linearly and blockingrotation of the plunger comprises a plunger block guide and a drivingnut.
 7. The automatic applicator according to claim 6, wherein theplunger block guide is blocked in a toothed ring of a seat element,urged by the housing of the exchangeable container.
 8. The automaticapplicator according to claim 1, wherein the tensioning spring is atwisted spring.
 9. The automatic applicator according to claim 1,wherein the tensioning spring is placed directly under the trigger unit.